Beware: Images, Video Shared on Signal Hang Around

Researcher John Jackson warned that Signal Desktop stores months' worth of reduced-resolution image and video previews unencrypted on disk and that cached media can persist after messages are deleted, potentially exposing sensitive attachments if a device is seized or compromised. Signal disputes the characterization as a new vulnerability, noting that at-rest encryption is the OS's responsibility and recommending full-disk encryption and standard device hardening; Jackson filed two CVEs and observers debated whether this behavior constitutes cleartext storage and incomplete cleanup.